Writing

Beyond Enumerable: Counting Distinct with HyperLogLog

Counting distinct values exactly means remembering all of them. HyperLogLog does it in 16 kilobytes. This post builds from coin flips to bitmaps to the algorithm Redis uses behind PFCOUNT.

Rails: The Sharp Parts. Queries, Read Models, and Batching

Queries own the reads the way commands own the writes, and a T::Struct is the only thing that crosses between them. Every read here ran against ActiveRecord 8.1 before it went in.

Rails: The Sharp Parts. Callbacks Are Not Invariants

Callbacks promise that something always happens when a record changes. They can't keep that promise, and Rails documents the ways out. Every failure mode here ran against ActiveRecord 8.1 before it went in, and the replacement is a command with one door.

Rails: The Sharp Parts. An Index Is Not a Plan

add_index looks like a one-line fix for slow queries. It isn't. This article walks through the failure modes, proves each one with EXPLAIN on half a million rows, and shows how to build an index the optimizer will actually use.

Beyond Enumerable: Streaming and External Sort

Enumerable assumes the whole collection fits in memory. This post is about what happens when it doesn't, built up one step at a time from lazy streams to external merge sort.

Beyond Enumerable: Graphs and Traversal

Enumerable named the ways we walk a line, but some data is not a line. This article builds graphs up from a plain Hash, covering dependency ordering, tsort, friend lists, and a few pathfinding algorithms.

Beyond Enumerable: Heaps and Priority Queues

Enumerable named our traversals, but some collections live past it. This post goes after ordered retrieval: heaps, priority queues, their real uses, and why they belong in Ruby itself.

Rails: The Sharp Parts. lock Is Not a Mutex

lock looks like a one-line fix for concurrency bugs. It isn't. This article walks through eight failure modes, proves each one with forking tests, and shows what actually holds an invariant.

Beyond Enumerable: For Want of Better Windows

Enumerable taught us a better path for iteration, what if we applied those lessons to other forms of iteration? This article covers windows and pointers.

AI Didn't Create These Problems. It Just Stopped Routing Around Them.

Every guardrail we need for AI is a good practice we should have already been doing. AI exposes the systemic gaps that experienced developers have been quietly routing around for years.

Grab the Chainsaw

A tornado flattened my town in 2011. What I learned that night still shapes how I show up to work today.

Noah Gibbs: Mentor, Friend, Ally

Content Warning: Death of a Ruby community member I woke up this morning to receive the news, among...

Let's Read - Eloquent Ruby - Ch 21 – Method Missing

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 22 – Method Missing Delegation

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 20 – Block Hooks

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 19 – Block Actions

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 18 – Block Wrapping

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 17 – Block Iterators

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 16 – Module Mixins

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 14 – Class Instance Variables

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 15 – Module Namespaces

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 13 – Singleton and Class Methods

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 11 – Operators

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 12 – Equality

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read - Eloquent Ruby - Ch 10 – Short Methods

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read – Eloquent Ruby – Ch 8 – Dynamic Typing

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read – Eloquent Ruby – Ch 9 – Tests

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read – Eloquent Ruby – Ch 7 – Objects

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

On Diligence

What is diligence? What does it mean to be diligent? It's a subject I've been reflecting on a good...

Understanding Ruby - Memoization

Introduction Memoization is a common technique in Ruby, but alas it's one with a few...

Beyond Senior - Metric Obsessions

After a number of conversations over the past few years with several other engineers who have moved...

Beyond Senior - Fire! Fire!

After a number of conversations over the past few years with several other engineers who have moved...

Beyond Senior - The Vista Problem

After a number of conversations over the past few years with several other engineers who have moved...

In Favor of Ruby Central Memberships

At the end of RailsConf this year Jonan and Ruby Central launched the Ruby Central Membership Program...

Pattern Matching Interfaces in Ruby

Defining a standard for implementing pattern matching interfaces in Ruby, originally from the 2021...

To Be Known for our Kindness

Content Warning: Death of a Ruby community member We have lost a great man in the Ruby community in...

Beyond Senior - The Parable of the Sword

After a number of conversations over the past few years with several other engineers who have moved...

New in Ruby 3.2 - Data.define

Victor Shepelev (Zverok) has just landed an extremely useful feature in Ruby, Data.define. You can...

On Promotions

On Promotions Ah yes, that time of year has come again, and with it come some of the most...

Beyond Senior – The Peacock, the Hermit, and the Counsel

After a number of conversations over the past few years with several other engineers who have moved...

Beyond Senior – The IC Misnomer

After a number of conversations over the past few years with several other engineers who have moved...

Beyond Senior – Just Enough Experimentation

After a number of conversations over the past few years with several other engineers who have moved...

Beyond Senior – Progressive Influence

After a number of conversations over the past few years with several other engineers who have moved...

Understanding Ruby – Recursion

To understand recursion, you must first understand recursion. Cute, but perhaps not the most useful...

On Autism - Grounding and Normalcy

Most of my writing on autism tends to pertain to software engineering in some regard, and while I...

ASTs in Ruby - Node Pattern and Introducing RuboCop

In the last article I was not being quite honest when I said that regex would not work when trying to...

ASTs in Ruby - Pattern Matching

Have you ever wanted to edit Ruby code programmatically? Perhaps change one bit of text to another,...

The Case for Pattern Matching Key Irreverence in Ruby

I had alluded to this post a bit earlier on Twitter, and in the Ruby bug tracker, but wanted to more...

Exploring dry-rb - Intuition of Results

dry-rb is a fascinating set of tools and libraries, but their usage may not be readily apparent. Why...

Ruby in FantasyLand: SumsUp

Javascript comes with this lovely little spec called Fantasy Land that defines certain type classes...

Tales of the Autistic Developer – The Politician

For those who don't know me, I'm autistic. I've been a developer for the better part of a decade. I...

Tales of the Autistic Developer – Order and Chaos

For those who don't know me, I'm autistic. I've been a developer for the better part of a decade. I...

Future of Ruby – AST Tooling

This is a series meant to explore the potential future of the Ruby programming language by visiting...

Let's Read – Eloquent Ruby – Ch 6 – Symbols

Let's Read – Eloquent Ruby – Ch 5 – Regular Expressions

Tales of the Autistic Developer - Loud Loud World

For those who don't know me, I'm autistic. I've been a developer for the better part of a decade. I...

Let's Read – Polished Ruby Programming – Ch 3.2 Instance Variables

Let's Read – Eloquent Ruby – Ch 4 – Smart Strings

Ruby 3.1 – Shorthand Hash Syntax – First Impressions

It's the time of year again, and with it comes a bundle of new Ruby 3.1 features getting approved and...

Let's Read – Eloquent Ruby – Ch 3 – Smart Collections

Let's Read – Polished Ruby Programming – Ch 3.1 – Local Variables

Functional Programming in Ruby – State

Ruby is, by nature, an Object Oriented language. It also takes a lot of hints from Functional...

Understanding Ruby - For vs Each

Introduction For those coming from other languages with for loops the concept of each,...

Let's Read – Polished Ruby Programming – Ch 2

Let's Read – Eloquent Ruby – Ch 2 – Control Structures

Let's Read – Eloquent Ruby – Ch 1 – Code That Looks Like Ruby

Perhaps my personal favorite recommendation for learning to program Ruby like a Rubyist, Eloquent...

Let's Read – Polished Ruby Programming – Ch 1

Polished Ruby Programming is a recent release by Jeremy Evans, a well known Rubyist working on the...

Interviewing - Perspective of the Interviewee

Interviewing in tech is hard, especially when you're just getting started. Years ago when I was getti...

Understanding Ruby - Enumerable - Coercion

Introduction Enumerable. Debatably one of, if not the, most powerful features in Ruby. As...

Understanding Ruby - Enumerable - Combining

Introduction Enumerable. Debatably one of, if not the, most powerful features in Ruby. As...

Understanding Ruby - Enumerable - Grouping

Introduction Enumerable. Debatably one of, if not the, most powerful features in Ruby. As...

Understanding Ruby - Enumerable - Iterating and Taking

Introduction Enumerable. Debatably one of, if not the, most powerful features in Ruby. As...

Understanding Ruby - Enumerable - Counting

Introduction Enumerable. Debatably one of, if not the, most powerful features in Ruby. As...

Understanding Ruby - Enumerable - Intro and Interfaces

Introduction Enumerable. Debatably one of, if not the, most powerful features in Ruby. As...

Understanding Ruby - Enumerable - Predicate Conditions

Introduction Enumerable. Debatably one of, if not the, most powerful features in Ruby. As...

Understanding Ruby - Enumerable - Searching and Filtering

Introduction Enumerable. Debatably one of, if not the, most powerful features in Ruby. As...

Understanding Ruby - Enumerable - Sorting and Comparing

Introduction Enumerable. Debatably one of, if not the, most powerful features in Ruby. As...

Understanding Ruby - Enumerable - Transformations

Introduction Enumerable. Debatably one of, if not the, most powerful features in Ruby. As...

Understanding Ruby - Comparable

Introduction Before we get into larger modules like Enumerable there are some very interes...

Understanding Ruby - to_proc and Function Interfaces

Introduction We've just covered the idea of Block Functions, Proc Functions, and Lambda Fu...

Definitive Pattern Matching - Array-like Structures

Introduction This is the start of a series on Ruby Pattern Matching, the goal of which is...

Understanding Ruby - Blocks, Procs, and Lambdas

Introduction Ruby is a language that uses multiple paradigms of programming, most usually...

Understanding Ruby - Triple Equals

Introduction Triple Equals (===) in Ruby is one of the most powerful features in the entir...

Matchable - Class-level Pattern Matching Macros Explained

Introduction Recently I've released a new gem, Matchable, which introduces class-level mac...

Ruby 3 Pattern Matching Applied: Tic-Tac-Toe

Pattern Matching in Ruby 2.7 and 3.0 can be an odd concept to read about, and an even stranger one to know how to use. This is another use case, this time to solve a Tic-Tac-Toe game

Ruby 3 Pattern Matching Applied: Poker

Pattern Matching in Ruby 2.7 and 3.0 can be an odd concept to read about, and an even stranger one to know how to use. This is a detailed example of a more complicated use-case of pattern matching to solve for scoring poker hands

Introducing Patterns in Parallelism for Ruby

With the advent of Ractor and Fibers we've hit the limits of mutable types. We're going to need some new patterns, and with that comes some interesting observations on the nature of parallel structures.

Advent of Ruby 3.0 - Day 06 - Custom Customs

An exploration into Ruby 2.7 and 3.0 features applied to Advent of Code Problems

Advent of Ruby 3.0 - Day 04 - Passport Processing

An exploration into Ruby 2.7 and 3.0 features applied to Advent of Code Problems

Advent of Ruby 3.0 - Day 05 - Binary Boarding

An exploration into Ruby 2.7 and 3.0 features applied to Advent of Code Problems

Advent of Ruby 3.0 - Day 03 - Toboggan Trajectory

An exploration into Ruby 2.7 and 3.0 features applied to Advent of Code Problems

Advent of Ruby 3.0 - Day 01 - Report Repair

An exploration into Ruby 2.7 and 3.0 features applied to Advent of Code Problems

Advent of Ruby 3.0 - Day 02 - Password Philosophy

An exploration into Ruby 2.7 and 3.0 features applied to Advent of Code Problems

Tales of the Autistic Developer - Becoming an Organizational Leader

A few months ago I'd announced my promotion, and in some of the replies I was asked what exactly I did to get to this point. This post covers my evolution at Square and how I've gotten to this point, as well as what I plan to do from here.

Tales of the Autistic Developer - The Expert

Autism can lead to obsession, and it isn't unusual that this evolves into expertise after enough practice, but how can this be leveraged effectively at work?

Ruby 3 - Set Literal

In our series on new Ruby 3.0 features we continue with the new Set literal syntax.

Tales of the Autistic Developer - The Mentor

People on the spectrum have a lot to share, but sometimes that sharing becomes a rapid information dump rather than something understandable by anyone else. How can someone on the spectrum mentor effectively, given this? These are a few of my strategies.

Ruby 3 - Anonymous Struct

In our series on new Ruby 3.0 features we start with the anonymous Struct, ${}.

Clocks are Monoids Too!

Along the theme of exploring FP concepts and interesting ideas we're taking another look at monoids in a specific sense: with clocks!

Tales of the Autistic Developer - Senior Developer

What does it take to become a Senior developer if you're on the spectrum? What does it look like once you're there? This is but one experience among many, but perhaps one that can help.

The Night Before Code Freeze

A new twist on a classic holiday poem with cartoon lemurs and fun to match

Deeper Magics: Monoids in Ruby and Rails

There exist some deeper magics and patterns in Ruby, this series will take a look at ideas from FP and how they can be applied.

Tales of the Autistic Developer - Myth of the Autistic Jerk

There's a myth that autistic people behave poorly, and that it's excusable because they're autistic. That's far from the truth.

The Nature of Success

What does it mean to be successful? Turns out that's complicated.

Decorating Ruby - Part Three - Prepending Decoration

How various forms of method decoration work in Ruby

Of a Higher Order - Map, Filter, Reduce

So you've seen map, filter, reduce, and other functions, but how do they work behind the scenes? Let's take a look

Decorating Ruby - Part Two - Method Added Decoration

How various forms of method decoration work in Ruby

Decorating Ruby - Part One - Symbol Method Decoration

How various forms of method decoration work in Ruby

Moving to Dev.To

Why I moved my writing to Dev.To and what I hope to get out of it.

How it's Made - Tales of the Ruby Grimoire

How my illustrated talk, "Tales of the Ruby Grimoire", was created.

Tales of the Ruby Grimoire - Part Five - On the Nature of Magic

Dark tales of Ruby magics from beyond what any sane Rubyist would teach in a book of legends, opened by a particularly curious young lemur named Red.

Tales of the Ruby Grimoire - Part Four - The Lemurs of Haskell

Dark tales of Ruby magics from beyond what any sane Rubyist would teach in a book of legends, opened by a particularly curious young lemur named Red.

Tales of the Ruby Grimoire - Part One - The Grimoire

Dark tales of Ruby magics from beyond what any sane Rubyist would teach in a book of legends, opened by a particularly curious young lemur named Red.

Tales of the Ruby Grimoire - Part Three - The Lemurs of Javascript

Dark tales of Ruby magics from beyond what any sane Rubyist would teach in a book of legends, opened by a particularly curious young lemur named Red.

Tales of the Ruby Grimoire - Part Two - The Lemurs of Scala

Dark tales of Ruby magics from beyond what any sane Rubyist would teach in a book of legends, opened by a particularly curious young lemur named Red.

Tales of the Autistic Developer - The 10x Engineer

With the recent debate over the 10x engineer, I see people like myself destroyed in pursuit of the myth. The danger is real, inhibitions are low, and many will burn out in the process.

Tales of the Autistic Developer - The Ecstasy of the Void

Lessons I wish I had learned when I was a new and Junior developer years ago, in the hopes that they'll help others avoid some of the same mistakes.

A Scoop of Sorbet - First Impressions

Stripe just released a new Ruby Static Typing library named Sorbet, let's take a look into it

Ruby 2.7: The Pipeline Operator

A pipeline operator has been added to Ruby, but not quite the one we'd expected

Ruby 2.7 — Pattern Matching — Destructuring on Point

Ruby 2.7 — Pattern Matching — Destructuring on Point Now that pattern matching has hit...

Ruby 2.7 — Pattern Matching — First Impressions

Ruby 2.7 — Pattern Matching — First Impressions Shall we grab a sneak peak at what Pattern...

Ruby 2.7 — Numbered Parameters

Ruby 2.7 — Numbered Parameters Ruby 2.7 is coming out this December, as with all modern...

Exploring TracePoint in Ruby — Part Two — Events

A comprehensive guide to every TracePoint event in Ruby — line, class, call, return, raise, block, thread, and fiber events with practical examples.

Ruby 2.7 — Enumerable#tally

Ruby 2.7 — Enumerable#tally Christmas has come and passed, 2.6 has been released, and now...

Exploring TracePoint in Ruby — Part One — Example Code

An introduction to TracePoint in Ruby — what it does, how it works, and practical examples of tracing code execution.

2018 in Review

A look back at 2018 — conference talks, open source projects, articles written, and adventures had.

Performance Test

Benchmarking different approaches to implementing select with reduce — push, shovel, and pure plus.

On On-Call, Operations, and Holidays

Thoughts on on-call culture, operations during the holidays, and building sustainable practices for engineering teams.

I want to paste in Pry!

Tips for pasting multi-line code into Pry, including using edit and pbpaste on Mac.

Sf — Abusing Operators and Method Missing

Taking operator abuse further with method_missing and custom proc coercion to build expressive DSLs.

Exploring Ruby 2.6 — Proc#compose and Enumerator#chain

Exploring Ruby 2.6 Proc#compose for function composition and Enumerator#chain for lazy enumeration.

Mf — Abusing Ruby’s Operator Precedence

Abusing Ruby's proc coercion and operator precedence to create expressive functional combinators.

RubyConf Rundown Pt. 1

A recap of favorite talks from RubyConf 2018, including Reducing Enumerable and other highlights.

Reducing Enumerable — Part Five: Cerulean, Master of Tally By

Part five of Reducing Enumerable — Cerulean teaches Red how to implement tally_by using reduce.

Reducing Enumerable — Part Four: Violet, Master of Find

Part four of Reducing Enumerable — Violet teaches Red how to implement find using reduce.

Reducing Enumerable — Part Six: A Final Lesson from Scarlet

The finale of Reducing Enumerable — Scarlet reveals the true nature of reduce and Red's journey comes full circle.

Reducing Enumerable — Part Three: Indigo, Master of Select

Part three of Reducing Enumerable — Indigo teaches Red how to implement select using reduce.

Reducing Enumerable — Part Two: Chartreuse, Master of Map

Part two of Reducing Enumerable — Chartreuse teaches Red the secrets of implementing map with reduce.

Exploring Ruby 2.6 — Enumerator, Hash, and Enumerable Changes

Exploring new Enumerable and Enumerator features in Ruby 2.6, including to_h with blocks and Enumerator chaining.

Lemurs mean Hope

The personal story behind the lemur illustrations — autism, mentorship, and how a group of lemurs became a symbol of hope.

Destructuring in Ruby

Implementing destructuring in Ruby using blocks, allowing methods to accept both keyword arguments and objects.

Let's Read! — Eloquent Ruby (Ch 2)

Reading through Eloquent Ruby Chapter 2 — choosing the right control structure, with modern Ruby updates.

Let's Read! — Eloquent Ruby (Ch 1)

Reading through Eloquent Ruby Chapter 1 — writing code that looks like Ruby, with notes on what has changed since 2011.

Understanding Transducers in Ruby

An introduction to transducers in Ruby — composable algorithmic transformations decoupled from their input sources.

Creating “Reducing Enumerable — An Illustrated Adventure”

Behind the scenes of creating a fully illustrated conference talk about reduce for Southeast Ruby 2018.

Challenge — Table of Contents Generator

A developer challenge to build a table of contents generator from HTML headers, with multiple solution approaches.

Tak — Sequencing Movesets in JS

Representing Tak board game moves as functional transformations in JavaScript.

Functional Programming in Ruby — Closures

Understanding closures in Ruby — how functions can capture and remember their surrounding context.

Functional Programming in Ruby — Flow Control

Functional approaches to flow control in Ruby, moving beyond exceptions to monadic error handling.

Qo::Evil — Dynamic Compilation with eval

Using eval to dynamically compile Qo pattern matches into native Ruby for near-vanilla performance.

On Dealing with Deep Hashes in Ruby — XF — Part Two: Traces

Part two of the Xf series, exploring Traces for recursively searching and transforming values in deep hashes.

On Dealing with Deep Hashes in Ruby — XF — Part One: Scopes

Introducing Xf, a Ruby gem for transforming deep hashes using functional scopes inspired by Haskell lenses.

The Developer Spectrum

A playful taxonomy of developer archetypes represented by different colored lemurs and their programming philosophies.

For want of Pattern Matching in Ruby — The Creation of Qo

The story behind creating Qo, a Ruby gem that brings pattern matching and fluent querying using triple equals.

New in Enumerable — Triple Equals Predicates

Exploring a Ruby proposal to add triple-equals predicate methods to Enumerable for more expressive filtering.

Reducing Enumerable — Sorting and State

Implementing sorting and stateful Enumerable functions using reduce, including quick sort and group_by.

Abusing Hash Constructors

Exploring the lesser-known features of Hash constructors in Ruby, from default values to block-based initialization.

Reducing Enumerable — No-Op and Boolean

Continuing the reduce series with no-op and boolean Enumerable functions implemented in terms of reduce.

Reducing Enumerable — The Basics

Every Enumerable method can be implemented with reduce. A beginner-friendly introduction to this powerful concept.

Triple Equals Black Magic

A deep dive into Ruby's triple equals operator and the surprising things you can do with it.